Slight RAM problem,

tekknow · 25 Jun 2011

When I built my computer I originaly had 2x2gb of Corsair XMS3 DDR3 1600 RAM in my P7P55D Deluxe motherboard. Recently I decided that I desired to upgrade from 4gb to 8gb and purchased the exact same RAM again. When I got the new sticks I noticed that the version was different from the original ones I purchased and its serial number was also different. The latest pair I got are CMX4GX3M2A1600C8 and v2.5 while the older pair are CMX4GX3M2A1600C9 v8.5. The timings are also different if I recall.

I isntalled the RAM anyways and thats where some small issues began to appear. For isntance upon booting my computer the computer will state "Detecting drives please wait..." this lasts for at least 3-5 minutes then states "No Drives found" then proceeds to boot to Windows. All my programs operate as usual (although Shogun 2: Total War has been crashing mysteriously) and I don't encounter the issue again until I reboot my computer.

My question would be, is this caused by the RAM being the same but just different versions of each other? Or does the motherboard just not like having 8gbs of RAM? The memory is registered on My Computer as 8gb.

PS: I also had a BSOD the today while Alt-Tab'ing Civilization 5 and the error message was "Memory_Management".

Any aid regarding my issue would be appreciated.

Britton30 · 25 Jun 2011

Yes you have one set at CAS 8 (new) and the old at CAS 9. the system will try to run all RAM at the lowest speed/CAS and may be causing conflicts.

Of course the new RAM may have one bad stick too. Run memtest on each stick and then with all installed. If you get errors, even one, Take sticks out one at a time and re-run the tests.

bobkn · 25 Jun 2011

Two things:

Using all four DIMM slots demands more of the motherboard than using just 2. Some RAM is OK in two slots, but not in 4. (See the QVL for your motherboard.)

The DIMM pairs aren't identical, so the board may not operate them together if you're relying on automatic settings. One possible solution would be to set the memory timing and voltage manually in the BIOS setup. Use the slower timings of either pair (9-9-9-24), and set the voltage to the rated value (1.65V). It may still fail, but it'll probably work.

I believe that you'd have to use something other than the default settings in the BIOS to get 1600MHz anyway. (It would default to 1333 or even 1066 MHz.)

Britton30's Memtest suggestion is a good one.

karlsnooks · 25 Jun 2011

Memtest86+ - Advanced Memory Diagnostic Tool

RAM - Test with Memtest86+